A new kind of ice: ‘amorphous’ solid, water ‘frozen in time’

February 7, 2023

Scientists have created a new type of ice, called medium-density amorphous ice ,that matches the density and structure of water.
The ice is called medium-density amorphous ice. The team that created it, led by Alexander Rosu-Finsen at University College London (UCL), shook regular ice in a small container with centimetre-wide stainless-steel balls at temperatures of (–) 200 °C to produce the variant, which has never been seen before. The ice appeared as a white granular powder that stuck to the metal balls.
Amorphous ice consists of water molecules arranged in a disordered state, with no large-scale regularity to their orientations or positions.
- This kind of ice is most often found in space, comets, interstellar clouds etc.
Normally, when water freezes, it crystallizes and its molecules are arranged into the familiar hexagonal, solid structure that we call ice. Ice is less dense than its liquid form — an unusual property for a crystal.
Depending on conditions such as pressure and the speed of freezing, water can also solidify in any of two dozen other regular arrangements.
- Amorphous ice is different: it has no such order.
Significance- Helps in studying water’s mysterious properties like Ice is less dense than its liquid form – an unusual property for a crystal.